The conventional vehicular door lock device has a lock lever connected to a key cylinder and an inner lock button (sill knob) so as to exchange the condition of the lock device from its locked one to its unlocked one. Ordinarily the lock lever can be changed by operations of the key cylinder or sill knob of a car owner. Somebody, for example, thieves can change or move the lock lever of the vehicular door lock device. In order to prevent the lock lever from being wrongly changed from the outside, various devices are employed to the conventional door lock device.
It is apparent that when the construction of the lock device provided with one lock lever connecting a key cylinder and a sill knob is improved to raise its crime preventability, the size of the lock device inevitably becomes larger.
U.S. Pat. No. 4,756,563 discloses a lock device provided with a lock lever having a key lock lever connected to a key cylinder and a sill knob lock lever connected to the sill knob. According to the conventional lock device disclosed in the U.S. Pat. No. 4,756,563, which employing two lock levers, it is possible to connect the key cylinder and the key lock lever through a rod or the like without any lost-motion. However, when the key cylinder and the key lock lever are connected without any lost-motion, the key lock lever becomes impossible the crime preventability very much. As described above, the conventional lock device having two lock levers has disadvantageously a number of constructional parts, but the size of the lock device relatively is small and its crime preventability is high.
However, the lock device disclosed in U.S. Pat. No. 4,756,563 has a shortcoming in that the key lock lever and the sill knob lock lever are rotatably journalled with a body of the lock device through a single shaft. That is, as shown in FIG. 13, in general, the inner side B of the body A of the conventional lock device has a high crime preventability and the outer side has a low preventability. A guide member for the door glass pane is placed at a central portion of the car body A and the guide member is a block for preventing unfair operation of the lock device from the outside, raising a crime preventability or safety of the interior side B.
Consequently, it is reasonable that the key lock lever is placed at the exterior side C of the vehicular room of low crime preventability and the sill knob lock lever is at the interior side B of high crime preventability, and these lock levers are journalled with different shafts, making the lock device of a high crime preventability or safe and of thin.